scholarly journals Genomic sequencing of Phyllosticta citriasiana provide insight into its conservation and diversification with closely related Phyllosticta species associated with citrus

2019 ◽  
Author(s):  
Mingshuang Wang ◽  
Bei Liu ◽  
Ruoxin Ruan ◽  
Yibing Zeng ◽  
Jinshui Luo ◽  
...  

AbstractPhyllosticta citriasiana is the causal agent of the pomelo tan spot. Here, we presented the ~34Mb genome of P. citriasiana. The genome is organized in 92 contigs, encompassing 9202 predicted genes. Comparative genomic analyses with other two Phyllosticta species (P. citricarpa and P. capitalensis) associated with citrus was conducted to understand their evolutionary conservation and diversification. Pairwise genome alignments revealed that these species are highly syntenic. All species encode similar numbers of CAZymes and secreted proteins. However, the molecular functions of the secretome showed that each species contains some enzymes with distinct activities. Three Phyllosticta species shared a core set of 7261 protein families. P. capitalensis had the largest set of orphan genes (2040), in complete contrast to that of P. citriasiana (371) and P. citricarpa (262). Most of the orphan genes were functionally unknown, but they contain a certain number of species-specific secreted proteins. A total of 23 secondary metabolites (SM) biosynthesis clusters were identified in the three Phyllosticta species, 21 of them are highly conserved among these species while the remaining 2 showed whole cluster gain and loss polymorphisms or gene content polymorphisms. Taken together, our study reveals insights into the genetic mechanisms of host adaptation of Phyllosticta species associated with citrus and paves the way to identify effectors that function in infection of citrus plants.

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Lisong Hu ◽  
Zhongping Xu ◽  
Maojun Wang ◽  
Rui Fan ◽  
Daojun Yuan ◽  
...  

Abstract Black pepper (Piper nigrum), dubbed the ‘King of Spices’ and ‘Black Gold’, is one of the most widely used spices. Here, we present its reference genome assembly by integrating PacBio, 10x Chromium, BioNano DLS optical mapping, and Hi-C mapping technologies. The 761.2 Mb sequences (45 scaffolds with an N50 of 29.8 Mb) are assembled into 26 pseudochromosomes. A phylogenomic analysis of representative plant genomes places magnoliids as sister to the monocots-eudicots clade and indicates that black pepper has diverged from the shared Laurales-Magnoliales lineage approximately 180 million years ago. Comparative genomic analyses reveal specific gene expansions in the glycosyltransferase, cytochrome P450, shikimate hydroxycinnamoyl transferase, lysine decarboxylase, and acyltransferase gene families. Comparative transcriptomic analyses disclose berry-specific upregulated expression in representative genes in each of these gene families. These data provide an evolutionary perspective and shed light on the metabolic processes relevant to the molecular basis of species-specific piperine biosynthesis.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Simin Chai ◽  
Ran Tian ◽  
Juanjuan Bi ◽  
Shixia Xu ◽  
Guang Yang ◽  
...  

Abstract Background The mammalian testis is an important male exocrine gland and spermatozoa-producing organ that usually lies in extra-abdominal scrotums to provide a cooler environment for spermatogenesis and sperm storage. Testicles sometimes fail to descend, leading to cryptorchidism. However, certain groups of mammals possess inherently ascrotal testes (i.e. testes that do not descend completely or at all) that have the same physiological functions as completely descended scrotal testes. Although several anatomical and hormonal factors involved in testicular descent have been studied, there is still a paucity of comprehensive research on the genetic mechanisms underlying the evolution of testicular descent in mammals and how mammals with ascrotal testes maintain their reproductive health. Results We performed integrative phenotypic and comparative genomic analyses of 380 cryptorchidism-related genes and found that the mammalian ascrotal testes trait is derived from an ancestral scrotal state. Rapidly evolving genes in ascrotal mammals were enriched in the Hedgehog pathway—which regulates Leydig cell differentiation and testosterone secretion—and muscle development. Moreover, some cryptorchidism-related genes in ascrotal mammals had undergone positive selection and contained specific mutations and indels. Genes harboring convergent/parallel amino acid substitutions between ascrotal mammals were enriched in GTPase functions. Conclusions Our results suggest that the scrotal testis is an ancestral state in mammals, and the ascrotal phenotype was derived multiple times in independent lineages. In addition, the adaptive evolution of genes involved in testicular descent and the development of the gubernaculum contributed to the evolution of ascrotal testes. Accurate DNA replication, the proper segregation of genetic material, and appropriate autophagy are the potential mechanisms for maintaining physiological normality during spermatogenesis in ascrotal mammals. Furthermore, the molecular convergence of GTPases is probably a mechanism in the ascrotal testes of different mammals. This study provides novel insights into the evolution of the testis and scrotum in mammals and contributes to a better understanding of the pathogenesis of cryptorchidism in humans.


BMC Genomics ◽  
2009 ◽  
Vol 10 (1) ◽  
pp. 358 ◽  
Author(s):  
Fumito Maruyama ◽  
Mitsuhiko Kobata ◽  
Ken Kurokawa ◽  
Keishin Nishida ◽  
Atsuo Sakurai ◽  
...  

2021 ◽  
Author(s):  
Hang Yu ◽  
Grayson L Chadwick ◽  
Usha F Lingappa ◽  
Jared Renton Leadbetter

Chemolithoautotrophic manganese oxidation has long been theorized, but only recently demonstrated in a bacterial co-culture. The majority member of the co-culture, Candidatus Manganitrophus noduliformans, is a distinct but not yet isolated lineage in the phylum Nitrospirota (Nitrospirae). Here, we established two additional MnCO3-oxidizing cultures using inocula from Santa Barbara (USA) and Boetsap (South Africa). Both cultures were dominated by strains of a new species, designated Candidatus Manganitrophus morganii. The next abundant members differed in the available cultures, suggesting that while Ca. Manganitrophus species have not been isolated in pure culture, they may not require a specific syntrophic relationship with another species. Phylogeny of cultivated Ca. Manganitrophus and related metagenome-assembled genomes revealed a coherent taxonomic family, Candidatus Manganitrophaceae, from both freshwater and marine environments and distributed globally. Comparative genomic analyses support this family being Mn(II)-oxidizing chemolithoautotrophs. Among the 895 shared genes were a subset of those hypothesized for Mn(II) oxidation (Cyc2 and PCC_1) and oxygen reduction (TO_1 and TO_2) that could facilitate Mn(II) lithotrophy. An unusual, plausibly reverse Complex 1 containing 2 additional pumping subunits was also shared by the family, as were genes for the reverse TCA carbon fixation cycle, which could enable Mn(II) autotrophy. All members of the family lacked genes for nitrification found in Nitrospira species. The results suggest that Ca. Manganitrophaceae share a core set of candidate genes for the newly discovered manganese dependent chemolithoautotrophic lifestyle, and likely have a broad, global distribution.


DNA Research ◽  
2020 ◽  
Vol 27 (4) ◽  
Author(s):  
Masato Nikaido ◽  
Shinji Kondo ◽  
Zicong Zhang ◽  
Jiaqi Wu ◽  
Hidenori Nishihara ◽  
...  

Abstract The revision of the sub-order Microchiroptera is one of the most intriguing outcomes in recent mammalian molecular phylogeny. The unexpected sister–taxon relationship between rhinolophoid microbats and megabats, with the exclusion of other microbats, suggests that megabats arose in a relatively short period of time from a microbat-like ancestor. In order to understand the genetic mechanism underlying adaptive evolution in megabats, we determined the whole-genome sequences of two rousette megabats, Leschenault’s rousette (Rousettus leschenaultia) and the Egyptian fruit bat (R. aegyptiacus). The sequences were compared with those of 22 other mammals, including nine bats, available in the database. We identified that megabat genomes are distinct in that they have extremely low activity of SINE retrotranspositions, expansion of two chemosensory gene families, including the trace amine receptor (TAAR) and olfactory receptor (OR), and elevation of the dN/dS ratio in genes for immunity and protein catabolism. The adaptive signatures discovered in the genomes of megabats may provide crucial insight into their distinct evolution, including key processes such as virus resistance, loss of echolocation, and frugivorous feeding.


2017 ◽  
Author(s):  
Jaaved Mohammed ◽  
Alex S. Flynt ◽  
Alexandra M. Panzarino ◽  
Md Mosharrof Hussein Mondal ◽  
Adam Siepel ◽  
...  

AbstractComparative genomic analyses of microRNAs (miRNAs) have yielded myriad insights into their biogenesis and regulatory activity. While miRNAs have been deeply annotated in a small cohort of model organisms, evolutionary assessments of miRNA flux are clouded by the functional uncertainty of orthologs in related species, and insufficient data regarding the extent of species-specific miRNAs. We address this by generating a comparative small RNA (sRNA) catalog of unprecedented breadth and depth across the Drosophila genus, extending our extant deep analyses of D. melanogaster with sRNA data from multiple tissues of 11 other fly species. Aggregate analysis of several billion sRNA reads permits curation of accurate and holistic compendia of miRNAs across this genus, providing abundant opportunities to identify species- and clade-specific variation in miRNA identity, abundance, and processing. Amongst well-conserved miRNAs, we observe unexpected cases of clade-specific variation in 5′ end precision, occasional antisense loci, and some putatively non-canonical loci. We also employ strict criteria to identify a massive set (649) of novel, evolutionarily-restricted miRNAs. Amongst the bulk collection of species-restricted miRNAs, two notable subpopulations of rapidly-evolving miRNAs are splicing-derived mirtrons and testis-restricted, clustered (TRC) canonical miRNAs. We quantify rates of miRNA birth and death using our annotation and a phylogenetic model for estimating rates of miRNA turnover in the presence of annotation uncertainty. We show striking differences in birth and death rates across miRNA classes defined by biogenesis pathway, genomic clustering, and tissue restriction, and even identify variation heterogeneity amongst Drosophila clades. In particular, distinct molecular rationales underlie the distinct evolutionary behavior of different miRNA classes. We broaden observations made from D. melanogaster as Drosophilid-wide principles for opposing evolutionary viewpoints for miRNA maintenance. Mirtrons are associated with a high rate of 3′ untemplated addition, a mechanism that impedes their biogenesis, whereas TRC miRNAs appear to evolve under positive selection. Altogether, these data reveal miRNA diversity amongst Drosophila species and permit future discoveries in understanding their emergence and evolution.


PLoS ONE ◽  
2013 ◽  
Vol 8 (6) ◽  
pp. e65670 ◽  
Author(s):  
Dea Shahinas ◽  
Christina S. Thornton ◽  
Gurdip Singh Tamber ◽  
Gitanjali Arya ◽  
Andrew Wong ◽  
...  

2014 ◽  
Vol 26 ◽  
pp. 274-282 ◽  
Author(s):  
Changsong Duan ◽  
Xiaolu Xiong ◽  
Yong Qi ◽  
Wenping Gong ◽  
Jun Jiao ◽  
...  

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